gistfile1.m

// 绘制几何体的形状,省略绘图代码
//  main.m
//  Shape-Procedural
//
//  Created by Novnan on 14-2-15.
//  Copyright (c) 2014年 Novnan. All rights reserved.
//

#import <Foundation/Foundation.h>

typedef enum { //定义几种不同的形状
    kCircle,
    kRectangle,
    kEgg } ShapeType;

typedef enum {  //定义几种颜色
    kRedColor,
    kGreenColor,
    kBlueColor } ShapeColor;

typedef struct {  //描述一个矩形，该矩形指定屏幕上的绘图区域
    int x, y, width, height;
} ShapeRect;

typedef struct {  //用结构体将前面的所有内容结合起来,整体描述一个形状
    ShapeType type;
    ShapeColor fillColor;
    ShapeRect bounds;
} Shape;

void drawShapes(Shape[], int);
NSString *colorName (ShapeColor);
int main(int argc, const char * argv[])
{  // 声明要绘制的形状数组

    Shape shapes[3];
    
    ShapeRect rect0 = { 0 , 0, 10, 30 };
    shapes[0].type = kCircle;
    shapes[0].fillColor = kRedColor;
    shapes[0].bounds = rect0;
    
    ShapeRect rect1 = { 30, 40, 50, 60 };
    shapes[1].type = kRectangle;
    shapes[1].fillColor = kGreenColor;
    shapes[1].bounds = rect1;
    
    ShapeRect rect2 = { 15, 18, 27, 29 };
    shapes[2].type = kEgg;
    shapes[2].fillColor = kBlueColor;
    shapes[2].bounds = rect2;
    
    drawShapes (shapes, 3);
    
    return (0);

} //main函数调用了drawShapes函数来绘制形状
void drawShapes (Shape shapes[], int count)
{
    for (int i = 0; i < count; i++){
        switch (shapes[i].type){
            case kCircle:
                drawCircle (shapes[i].bounds, shapes[i].fillColor);
                break;
            case kRectangle:
                drawRectangle (shapes[i].bounds, shapes[i].fillColor);
                break;
            case kEgg:
                DrawEgg (shapes[i].bounds, shapes[i].fillColor);
                break;
        }
    }
}
void drawCirlce (ShapeRect, ShapeColor);
//下面是drawCircle()函数的代码，此函数输出矩形区域信息的传递给它的颜色

void drawCirlce (ShapeRect bounds, ShapeColor fillcolor)
    {
        NSLog(@"drawing a circle at (%d %d %d %d) in %@", bounds.x, bounds.y, bounds.width, bounds.height,
              colorName(fillcolor));
    }
// NSlog()中调用的colorName()函数负责转换传入的颜色值，并返回NSString字面量，比如@"red" 或 @"bule"
                
NSString *colorName (ShapeColor colorName)
    {
        switch (colorName) {
            case kRedColor:
                return @"red";
                break;
            case kGreenColor:
                return @"green";
                break;
            case kBlueColor:
                return @"blue";
                break;
        }
        return @"no clue";
    }